The present invention relates to an image photographing apparatus, particularly to an image photographing apparatus having a simple and small structure mounted on a communication terminal.
FIG. 1 is a block diagram explaining the constitution of the conventional image photographing apparatus. As shown in FIG. 1, a mobile phone 100 comprises: a main frame 101; buttons 102 for operating the mobile phone, a screen 103 for displaying telephone numbers or images, and a camera module 104 for photographing images. The interior constitution of the camera module 104 is shown in FIG. 2. That is, the camera module 104 comprises a module case 201, a photographing element 203, a second lens group 206, and a third lens group 207. FIG. 3 is a view separating a photographing optical system 300, which comprises a moiré interference prevention filter 202, the first lens group 205, the second lens group 206 and the third lens group 207, from the camera module 200 to explain the function thereof. The photographing optical system 300 photographs an image of an object positioned on an object surface 301 on an image plane 303. Accordingly, the photographing element 203 is positioned on the image plane 303, and thus an object 302 on the object surface 301 is formed as an image 304 on the image surface 303.
As shown in FIG. 4 showing the conventional constitution, if an object 401 escapes from the object surface 301 and positions near the camera, the image of the object 401 is formed apart from the image surface 303. On the contrary, as shown in FIG. 5, if an object 501 escapes from the object surface 301 and positions far from the camera, the image 501 of the object escapes from the image plane and moves along the direction which is near the photographing optical system 300. As above, if the object escapes from the object surface initially set by the photographing optical system 300, the image of the object also escapes from the image plane 303. Thus, the photographed image is. out of focus and the quality of the photographed image becomes worse.